hello. my question is this:
2x-y+3=1
-x-3y+2z=-4
-3x+y+7z=-2
yes, that's what he's talking about. i will go all the way to reduced row echelon, i like doing that.
ok, here goes. i will not type what i did to get from one step to another, so if you don't understand something, just ask.
The augmented matrix is:
...$\displaystyle x$.....$\displaystyle y$....$\displaystyle z$
$\displaystyle \left| \begin {array}{ccc|c} 2 & {-1} & 3& 1 \\ {-1}&{-3} & 2& {-4} \\ {-3}&1 &7 &{-2} \end {array} \right|$
$\displaystyle \left| \begin {array}{ccc|c} 1& 3& {-2}& 4\\ 0& -7& 7&-7 \\ 0& 10&1 &10 \end {array} \right|$
$\displaystyle \left| \begin {array}{ccc|c} 1& 3& -2&4 \\ 0& 1& -1&1 \\ 0& 10& 1&10 \end {array} \right|$
$\displaystyle \left| \begin {array}{ccc|c} 1& 0& 1&1 \\ 0& 1& -1&1 \\ 0& 0& 11& 0\end {array} \right|$
$\displaystyle \left| \begin {array}{ccc|c} 1& 0& 1&1 \\ 0&1 &0 &1 \\ 0& 0& 1& 0\end {array} \right|$
$\displaystyle \left| \begin {array}{ccc|c} 1& 0& 0&1 \\ 0& 1&0 &1 \\ 0& 0& 1& 0\end {array} \right|$
now read off your solutions...